Method for manufacturing thin film transistor, method for manufacturing array substrate, array substrate and display device

ABSTRACT

A method for manufacturing thin film transistor, a method for manufacturing array substrate, an array substrate and a display device are provided. The method for manufacturing thin film transistor includes forming an intermediate layer on a substrate, patterning the intermediate layer to form an intermediate layer reserved region and an intermediate layer unreserved region, where the intermediate layer unreserved region corresponds to a pattern of a first structure layer, forming, on the substrate with a pattern of the intermediate layer, a material layer from which the first structure layer is formed, and removing the intermediate layer, and forming the pattern of the first structure layer through a portion of the material layer remaining on the substrate.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the U.S. national phase of PCT Application No.PCT/CN2016/081424 filed on May 9, 2016, which claims priority to ChinesePatent Application No. 201610073355.2 filed on Feb. 2, 2016, thedisclosures of which are incorporated in their entirety by referenceherein.

TECHNICAL FIELD

The present disclosure relates to the field of display technology, andin particular to a method for manufacturing a thin film transistor, amethod for manufacturing an array substrate, an array substrate and adisplay device.

BACKGROUND

A method for manufacturing an array substrate in the related artincludes forming on a base substrate a pattern of a gate metal layer, apattern of an active layer, a pattern of a source and drain metal layer,a pattern of a passivation layer and a pattern of a transparentconductive layer in order, and each pattern of the above layers ismanufactured through such steps as depositing and coating a photoresist,exposing, developing, etching and removing the photoresist and the like.

In a manufacturing process, foreign matters such as dust and chippingsare inescapably attached onto the film layers due to the environment,device and other abnormal factors. Theses foreign matters may beattached during the depositing process, the photoresist coating processor the dry etching process. When etching the active layer by the dryetching process, an etching gas may not contact the active layer andreact with the same due to the foreign matters attached thereon, andthen the portions of the active layer attached with the foreign mattersmay be remained. As a result, light spots may occur, and the yield ofthe array substrate may be affected adversely.

SUMMARY

An object of the present disclosure is to provide a method formanufacturing a thin film transistor, a method for manufacturing anarray substrate, an array substrate and a display device, so as to avoidthe residual film layer and improve the yield of the array substrate.

To achieve the above object, the present disclosure provides thefollowing solutions.

A method for manufacturing a thin film transistor is provided,including: forming an intermediate layer on a substrate; patterning theintermediate layer to form an intermediate layer reserved region and anintermediate layer unreserved region, where the intermediate layerunreserved region corresponds to a pattern of a first structure layer;forming, on the substrate with a pattern of the intermediate layer, amaterial layer from which the first structure layer is formed; andremoving the intermediate layer, and forming the pattern of the firststructure layer through a portion of the material layer remaining on thesubstrate.

Optionally, the intermediate layer reserved region has a surface with aconcave-convex structure.

Optionally, a height difference between a convex portion and a concaveportion of the concave-convex structure is larger than a thickness ofthe first structure layer.

Optionally, a material of the intermediate layer includes a photoresist.

Optionally, the first structure layer is an active layer.

Optionally, the intermediate layer is a positive photoresist, and thestep of forming the intermediate layer reserved region with theconcave-convex structure includes: exposing the intermediate layer by agrey tone mask plate including an opaque region, a semi-transparentregion and a transparent region; and forming, after a developingprocess, a first portion of the intermediate layer reserved regioncorresponding to the opaque region, a second portion of the intermediatelayer reserved region corresponding to the semi-transparent region andthe intermediate layer unreserved region corresponding to thetransparent region. A thickness of the first portion is larger than athickness of the second portion.

Optionally, the intermediate layer is a negative photoresist, and thestep of forming the intermediate layer reserved region with theconcave-convex structure includes: exposing the intermediate layer by agrey tone mask plate including an opaque region, a semi-transparentregion and a transparent region; and forming, after a developingprocess, a first portion of the intermediate layer reserved regioncorresponding to the transparent region, a second portion of theintermediate layer reserved region corresponding to the semi-transparentregion and the intermediate layer unreserved region corresponding to theopaque region. A thickness of the first portion is larger than athickness of the second portion.

Optionally, the step of removing the intermediate layer includes:applying a stripping liquid onto an exposed portion of the intermediatelayer, and removing the intermediate layer from the substrate through achemical reaction between the stripping liquid and the intermediatelayer.

Optionally, the step of removing the intermediate layer, and forming thepattern of the first structure layer through a portion of the materiallayer remaining on the substrate includes: coating a photoresist ontothe material layer; exposing the photoresist using a mask plate, andforming, after a developing process, a photoresist reserved region and aphotoresist unreserved region, where the photoresist reserved regioncorrespond to the pattern of the first structure layer; removing thematerial layer corresponding to the photoresist unreserved region by adry etching process; and applying a stripping liquid onto an exposedportion of the intermediate layer, and removing the intermediate layerfrom the substrate through a chemical reaction between the strippingliquid and the intermediate layer.

Optionally, a material of the intermediate layer includes a photoresist.

Optionally, the first structure layer is an active layer.

Optionally, the intermediate layer is a positive photoresist, and thestep of forming the intermediate layer reserved region with theconcave-convex structure includes: exposing the intermediate layer by agrey tone mask plate including an opaque region, a semi-transparentregion and a transparent region; and forming, after a developingprocess, a first portion of the intermediate layer reserved regioncorresponding to the opaque region, a second portion of the intermediatelayer reserved region corresponding to the semi-transparent region andthe intermediate layer unreserved region corresponding to thetransparent region. A thickness of the first portion is larger than athickness of the second portion.

Optionally, the intermediate layer is a negative photoresist, and thestep of forming the intermediate layer reserved region with theconcave-convex structure includes: exposing the intermediate layer by agrey tone mask plate including an opaque region, a semi-transparentregion and a transparent region; and forming, after a developing, afirst portion of the intermediate layer reserved region corresponding tothe transparent region, a second portion of the intermediate layerreserved region corresponding to the semi-transparent region and theintermediate layer unreserved region corresponding to the opaque region.A thickness of the first portion is larger than a thickness of thesecond portion.

Optionally, the step of removing the intermediate layer includes:applying a stripping liquid onto an exposed portion of the intermediatelayer, and removing the intermediate layer from the substrate through achemical reaction between the stripping liquid and the intermediatelayer.

Optionally, a material of the material layer includes a-Si and N+a-Si.

Optionally, prior to forming an intermediate layer on a substrate, themethod further includes: providing a base substrate; forming a patternof a gate metal layer on the substrate; and depositing a gate insulatinglayer onto the base substrate provided with the pattern of the gatemetal layer.

A method for manufacturing an array substrate is provided, includingforming a thin film transistor on a substrate by the method hereinabove.

An array substrate is provided, including a thin film transistor formedon a substrate by the method hereinabove.

A display device is provided, including the array substrate hereinabove.

According to the present disclosure, a pattern of an intermediate layeris formed on a substrate. The pattern of the intermediate layer includesan intermediate layer reserved region and an intermediate layerunreserved region. The intermediate layer unreserved region correspondsto a pattern of an active layer. A material of the active layer isdeposited onto the substrate with the pattern of the intermediate layer.Therefore, the pattern of the active layer may be formed after theintermediate layer is removed. According to the present disclosure, thepattern of the active layer is formed by removing the intermediate layerrather than etching the material of the active layer by a dry etchingprocess, therefore the residue of the active layer film may be avoidedeven though there are foreign matters attached on the material of theactive layer, thereby improving the yield of the array substrate.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a base substrate with a pattern of a gatemetal layer arranged thereon in some embodiments of the presentdisclosure;

FIG. 2 is a schematic view where a gate insulating layer is formed insome embodiments of the present disclosure;

FIG. 3 is a schematic view where a photoresist is formed in someembodiments of the present disclosure;

FIG. 4 is a schematic view where an active layer is deposited on thephotoresist in some embodiments of the present disclosure;

FIG. 5 is a schematic view where a photoresist is removed and a patternof an active layer is formed in some embodiments of the presentdisclosure;

FIG. 6 is a schematic view where a photoresist is coated on a gateinsulating layer in some embodiments of the present disclosure;

FIG. 7 is a schematic view where a photoresist is etched in someembodiments of the present disclosure;

FIG. 8 is a schematic view where an active layer is deposited on aphotoresist in some embodiments of the present disclosure;

FIG. 9 is a schematic view where a photoresist is coated on the activelayer in some embodiments of the present disclosure;

FIG. 10 is a schematic view where a photoresist coated on the activelayer is etched in some embodiments of the present disclosure; and

FIG. 11 is a schematic view where an active layer is etched in someembodiments of the present disclosure.

DRAWING REFERENCES

-   1: base substrate; 2: gate metal layer; 3: gate insulating layer; 4:    active layer; 10: photoresist

DETAILED DESCRIPTION

In order to make the objects, the technical solutions and the advantagesof the present disclosure more apparent, the present disclosure will bedescribed hereinafter in details in conjunction with the drawings andembodiments. Obviously, the following embodiments merely relate to apart of, rather than all of, the embodiments of the present disclosure,and based on these embodiments, a person skilled in the art may, withoutany creative effort, obtain the other embodiments, which also fallwithin the scope of the present disclosure.

Unless otherwise defined, any technical or scientific term used hereinshall have the common meaning understood by a person of ordinary skills.Such words as “first” and “second” used in the specification and claimsare merely used to differentiate different components rather than torepresent any order, number or importance. Similarly, such words as“one” or “one of” are merely used to represent the existence of at leastone member, rather than to limit the number thereof. Such words as“connect” or “connected to” may include electrical connection, direct orindirect, rather than to be limited to physical or mechanicalconnection. Such words as “on”, “under”, “left” and “right” are merelyused to represent relative position relationship, and when an absoluteposition of the object is changed, the relative position relationshipwill be changed too.

In the related art, an a-Si layer and an N+a-Si layer are deposited inorder onto an gate insulating layer (which may be made of SiNx) whileforming a pattern of an active layer. Then, a photoresist is coated ontothe N+a-Si layer. After an exposing process and a developing process,the photoresist above a region of the active layer pattern is remained,and the photoresist above the other regions is removed. Then, the a-Silayer and the N+a-Si layer which are not protected by the photoresistare removed by a dry etching process. At last, the remained photoresistis removed by a liquid reaction, so as to form the pattern of the activelayer. In a manufacturing process, foreign matters such as dust andchippings are inescapably attached onto the film layers due to theenvironment, device and other abnormal factors. Theses foreign mattersmay be attached during the depositing process, the photoresist coatingprocess or the dry etching process. When etching the active layer by thedry etching process, an etching gas may not contact the active layer andreact with the same due to the foreign matters attached thereon, andthen the portions of the active layer attached with the foreign mattersmay be remained. As a result, light spots may occur, and the yield ofthe array substrate may be affected adversely.

A method for manufacturing a thin film transistor, a method formanufacturing array substrate, an array substrate and a display deviceare provided in some embodiments of the present disclosure, to solve theissues in the related art that the residue of the active layer filmresults in light spots and adversely affects the yield of the arraysubstrate, so as to avoid the residue of the film layer and improve theyield of the array substrate.

A method for manufacturing a thin film transistor is provided in someembodiments of the present disclosure, including: forming anintermediate layer on a substrate; patterning the intermediate layer toform an intermediate layer reserved region and an intermediate layerunreserved region, where the intermediate layer unreserved regioncorresponds to a pattern of a first structure layer and the intermediatelayer reserved region has a surface with a concave-convex structure;forming, on the substrate with a pattern of the intermediate layer, amaterial layer from which the first structure layer is formed; andremoving the intermediate layer, and forming the pattern of the firststructure layer through a portion of the material layer remaining on thesubstrate.

According to the embodiments of the present disclosure, a pattern of anintermediate layer is formed on a substrate. The pattern of theintermediate layer includes an intermediate layer reserved region and anintermediate layer unreserved region. The intermediate layer unreservedregion corresponds to a pattern of an active layer. A material of theactive layer is deposited onto the substrate with the pattern of theintermediate layer. Therefore, the pattern of the active layer may beformed after the intermediate layer is removed. According to theembodiments of the present disclosure, the pattern of the active layeris formed by removing the intermediate layer rather than etching thematerial of the active layer by a dry etching process, therefore theresidue of the active layer film may be avoided even though foreignmatters are attached on the material of the active layer, therebyimproving the yield of the array substrate.

In some embodiments of the present disclosure, the intermediate layermay be made of a photoresist.

In some embodiments of the present disclosure, the first structure layermay be but not limited to an active layer. In the case that the firststructure layer is an active layer, the residue of the active layer filmmay be avoided and the yield of the array substrate may be improvedeffectively.

Optionally, the intermediate layer is a positive photoresist, and thestep of forming the intermediate layer reserved region with theconcave-convex structure includes: exposing the intermediate layer by agrey tone mask plate including an opaque region, a semi-transparentregion and a transparent region; and forming, after a developingprocess, a first portion of the intermediate layer reserved regioncorresponding to the opaque region, a second portion of the intermediatelayer reserved region corresponding to the semi-transparent region andthe intermediate layer unreserved region corresponding to thetransparent region. Here, a thickness of the first portion is largerthan a thickness of the second portion.

Optionally, the intermediate layer is a negative photoresist, and thestep of forming the intermediate layer reserved region with theconcave-convex structure includes: exposing the intermediate layer by agrey tone mask plate including an opaque region, a semi-transparentregion and a transparent region; and forming, after a developingprocess, a first portion of the intermediate layer reserved regioncorresponding to the transparent region, a second portion of theintermediate layer reserved region corresponding to the semi-transparentregion and the intermediate layer unreserved region corresponding to theopaque region. Here, a thickness of the first portion is larger than athickness of the second portion.

Optionally, the step of removing the intermediate layer includes:applying a stripping liquid onto an exposed portion of the intermediatelayer, and removing the intermediate layer from the substrate through achemical reaction between the stripping liquid and the intermediatelayer.

Optionally, the step of removing the intermediate layer, and forming thepattern of the first structure layer through a portion of the materiallayer remaining on the substrate, includes: coating a photoresist ontothe material layer; exposing the photoresist using a mask plate, andforming, after a developing process, a photoresist reserved region and aphotoresist unreserved region, where the photoresist reserved regioncorrespond to the pattern of the first structure layer; removing thematerial layer corresponding to the photoresist unreserved region by adry etching process; and applying a stripping liquid onto an exposedportion of the intermediate layer, and removing the intermediate layerfrom the substrate through a chemical reaction between the strippingliquid and the intermediate layer.

Accordingly, even though the residue of the active layer film occurs dueto the foreign matters at the photoresist unreserved region, the residueof the active layer film may be guaranteed to be peeled off in thesubsequent process of removing the intermediate layer. According to themethod hereinabove, it is not required to form an intermediate layerreserved region having a concave-convex surface, thereby simplifying themanufacturing process.

In some embodiments of the present disclosure, the material layer may bemade of a-Si layer and N+a-Si.

A method for manufacturing an array substrate is provided in someembodiments of the present disclosure, including forming a thin filmtransistor on a substrate by the method hereinabove.

According to the embodiments of the present disclosure, a pattern of anintermediate layer is formed on a substrate. The pattern of theintermediate layer includes an intermediate layer reserved region and anintermediate layer unreserved region. The intermediate layer unreservedregion corresponds to a pattern of an active layer. A material of theactive layer is deposited onto the substrate with the pattern of theintermediate layer. Therefore, the pattern of the active layer may beformed after the intermediate layer is removed. According to theembodiments of the present disclosure, the pattern of the active layeris formed by removing the intermediate layer rather than etching thematerial of the active layer by a dry etching process, therefore theresidue of the active layer film may be avoided even though foreignmatters are attached on the material of the active layer, therebyimproving the yield of the array substrate.

An array substrate is provided in some embodiments, including a thinfilm transistor formed on a substrate by the method hereinabove.According to the array substrate provided, the residue of the activelayer film may not occur and the yield of the array substrate may beimproved effectively.

A display device is provided in some embodiments, including the arraysubstrate hereinabove. The display device may be any product orcomponent with a display function, such as a liquid crystal television,a liquid crystal display, a digital photo frame, a cell phone and atablet PC. The display device may include a flexible circuit board, aprinted circuit board and a back plate.

A method for manufacturing an array substrate is provided in someembodiments of the present disclosure, so as to avoid the light spotsdue to the residue of the active layer film. The method includes Steps1-5 in the following.

Step 1: providing a base substrate 1 and forming a pattern of a gatemetal layer 2 on the base substrate 1, as shown in FIG. 1;

Step 2: depositing a gate insulating layer 3 on the resultant basesubstrate 1 in Step 1, to avoid a short circuiting of the gate metallayer 2, as shown in FIG. 2;

Step 3: coating a photoresist 10 on the resultant base substrate 1 inStep 2 and exposing the photoresist 10 by a grey tone mask plate, andforming, after a developing process, a photoresist unreserved regioncorresponding to a pattern of an active layer and a photoresist reservedregion corresponding to the other regions, where the photoresistreserved region includes a first portion 11 and a second portion 12, andthe first portion 11 and the second portion 12 have differentthicknesses, so as to form a pit-like photoresist reserved region, i.e.,the photoresist reserved region has an uneven surface, as shown in FIG.3;

Step 4: depositing an active layer 4 on the resultant base substrate 1in Step 3, as shown in FIG. 4. The active layer 4 includes an a-Si layerand an N+a-Si layer. There is no photoresist at the photoresistunreserved region, so the deposited active layer 4 may be in directcontact with the gate insulating layer 3. The active layer at the otherregions is deposited onto the photoresist 10. The photoresist reservedregion has the surface with the concave-convex structure, and a heightdifferent between a top and a bottom of the concave-convex structure islarger than a thickness of the active layer 4, so the film of the activelayer 4 may be in a disconnected state i.e., loss of continuity, duringthe depositing of the active layer 4. And then some photoresist coveredby the active layer 4 may be exposed, thereby the stripping liquid mayby in contact with the photoresist and reacts with the same in thesubsequent removing process;

Step 5: applying a stripping liquid onto the photoresist 10 to removethe photoresist 10. According to the embodiments of the presentdisclosure, the active layer 4 is deposited on the photoresist 10, sothere is no need to etch the deposited active layer 4 by a dry etchingprocess. After removing the photoresist 10, the active layer 4 at thephotoresist reserved region may be removed correspondingly, and then thepattern of the active layer 4 is formed.

According to the embodiments of the present disclosure, a layer ofphotoresist is coated on the gate insulating layer, the photoresist atthe region of the active layer pattern is removed, the photoresist atthe other regions is formed to have a concave-convex surface, and thenthe active layer is deposited. Since the photoresist has aconcave-convex surface, during the depositing of the active layer, partsof the active layer may be disconnected at interfaces of an upperportion and a lower portion of the photoresist, such that thephotoresist under the active layer may be exposed. The photoresist isremoved through a chemical reaction between the stripping liquid and thephotoresist, and then the active layer deposited on the photoresist isremoved, while the active layer deposited on the photoresist unreservedregion is not removed, so as to form the pattern of the active layer.According to the embodiments of the present disclosure, the pattern ofthe active layer is formed by removing the intermediate layer ratherthan etching the material of the active layer by a dry etching process.Therefore the residue of the active layer film may be avoided eventhough foreign matters are attached on the material of the active layer,thereby improving the yield of the array substrate.

In some embodiments of the present disclosure, a method formanufacturing an array substrate is provided in some embodiments of thepresent disclosure, so as to avoid the light spots due to the residue ofthe active layer film. The method includes Steps 1-9 in the following.

Step 1: providing a base substrate 1 and forming a pattern of a gatemetal layer 2 on the base substrate 1, as shown in FIG. 1;

Step 2: depositing a gate insulating layer 3 on the resultant basesubstrate 1 in Step 1, to avoid a short circuiting of the gate metallayer 2, as shown in FIG. 2;

Step 3: coating a photoresist 10 on the resultant base substrate 1 inStep 2, as shown in FIG. 6;

Step 4: exposing the photoresist 10, and forming, after a developingprocess, a photoresist unreserved region corresponding to a pattern ofan active layer and a photoresist reserved region corresponding to theother regions, as shown in FIG. 7;

Step 5: depositing an active layer 4 on the resultant base substrate 1in Step 4, as shown in FIG. 8, where the active layer 4 includes an a-Silayer and an N+a-Si layer. There is no photoresist at the photoresistunreserved region, so the active layer 4 deposited at the photoresistunreserved region may be in direct contact with the gate insulatinglayer 3;

Step 6: depositing a photoresist 10 on the resultant base substrate 1 inStep 5, as shown in FIG. 9;

Step 7: exposing the photoresist 10, and forming, after a developingprocess, a photoresist reserved region corresponding to the pattern ofthe active layer and a photoresist unreserved region corresponding tothe other regions, as shown in FIG. 10;

Step 8: removing the active layer 4 at the photoresist unreserved regionby a dry etching process, to form a pattern of the active layer 4, asshown in FIG. 11;

Step 9: applying a stripping liquid onto the photoresist 10 to removethe photoresist 10, as shown in FIG. 5.

Accordingly, even though the residue of the active layer film occurs dueto the foreign matters at the other region, the residue of the activelayer film may be guaranteed to be peeled off in the subsequent processof removing the intermediate layer since the active layer is formed onthe photoresist. According to the method hereinabove, it is not requiredto form an intermediate layer reserved region having a concave-convexsurface, thereby simplifying the manufacturing process.

The above are merely the preferred embodiments of the presentdisclosure. A person skilled in the art may make further modificationsand improvements without departing from the principle of the presentdisclosure, and these modifications and improvements shall also fallwithin the scope of the present disclosure.

What is claimed is:
 1. A method for manufacturing a thin filmtransistor, comprising: forming an intermediate layer on a substrate;patterning the intermediate layer to form an intermediate layer reservedregion and an intermediate layer unreserved region, wherein theintermediate layer unreserved region corresponds to a pattern of a firststructure layer; forming, on the substrate with a pattern of theintermediate layer, a material layer from which the first structurelayer is formed; and removing the intermediate layer, and forming thepattern of the first structure layer through a portion of the materiallayer remaining on the substrate, wherein the intermediate layerreserved region has a surface with a concave-convex structure, and amaterial of the intermediate layer comprises a photoresist.
 2. Themethod according to claim 1, wherein a height difference between aconvex portion and a concave portion of the concave-convex structure islarger than a thickness of the first structure layer.
 3. The methodaccording to claim 1, wherein the first structure layer is an activelayer.
 4. The method according to claim 3, wherein the intermediatelayer is a positive photoresist, and the step of forming theintermediate layer reserved region comprises: exposing the intermediatelayer by a grey tone mask plate comprising an opaque region, asemi-transparent region and a transparent region; and forming, after adeveloping process, a first portion of the intermediate layer reservedregion corresponding to the opaque region, a second portion of theintermediate layer reserved region corresponding to the semi-transparentregion and the intermediate layer unreserved region corresponding to thetransparent region, wherein a thickness of the first portion is largerthan a thickness of the second portion.
 5. The method according to claim3, wherein the intermediate layer is a negative photoresist, and thestep of forming the intermediate layer reserved region comprises:exposing the intermediate layer by a grey tone mask plate comprising anopaque region, a semi-transparent region and a transparent region; andforming, after a developing process, a first portion of the intermediatelayer reserved region corresponding to the transparent region, a secondportion of the intermediate layer reserved region corresponding to thesemi-transparent region and the intermediate layer unreserved regioncorresponding to the opaque region, wherein a thickness of the firstportion is larger than a thickness of the second portion.
 6. The methodaccording to claim 3, wherein the step of removing the intermediatelayer comprises: applying a stripping liquid onto an exposed portion ofthe intermediate layer, and removing the intermediate layer from thesubstrate through a chemical reaction between the stripping liquid andthe intermediate layer.
 7. The method according to claim 1, wherein amaterial of the material layer comprises a-Si and N+a-Si.
 8. The methodaccording to claim 1, wherein prior to forming an intermediate layer ona substrate, the method further comprises: providing a base substrate;forming a pattern of a gate metal layer on the substrate; and depositinga gate insulating layer onto the base substrate provided with thepattern of the gate metal layer.
 9. A method for manufacturing an arraysubstrate, comprising forming a thin film transistor on a substrate bythe method according to claim
 1. 10. An array substrate, comprising athin film transistor formed on a substrate by the method according toclaim
 1. 11. A display device, comprising the array substrate accordingto claim
 10. 12. The method according to claim 1, wherein prior toforming an intermediate layer on a substrate, the method furthercomprises: providing a base substrate; forming a pattern of a gate metallayer on the substrate; and depositing a gate insulating layer onto thebase substrate provided with the pattern of the gate metal layer.
 13. Amethod for manufacturing a thin film transistor, comprising: providing asubstrate; forming a pattern of a gate metal layer on the substrate;depositing a gate insulating layer onto the substrate provided with thepattern of the gate metal layer; coating a first intermediate layer onthe substrate; exposing the first intermediate layer and forming, aftera developing process, a first intermediate layer unreserved regioncorresponding to a pattern of a first structure layer and a firstintermediate layer reserved region corresponding to other regions;depositing the first structure layer on the substrate; depositing asecond intermediate layer on the substrate; exposing the secondintermediate layer, and forming, after a developing process, a secondintermediate layer reserved region corresponding to the pattern of thefirst structure and a second intermediate layer unreserved regioncorresponding to the other regions; removing the first structure layerat the second intermediate layer unreserved region by a dry etchingprocess, to form a pattern of the first structure layer; and applying astripping liquid onto the second intermediate layer to remove the firstintermediate layer and the second intermediate layer, wherein theintermediate layer reserved region has a surface with a concave-convexstructure, and each of a material of the first intermediate layer and amaterial of the second intermediate layer comprises a photoresist. 14.The method according to claim 13, wherein the first structure layer isan active layer.
 15. The method according to claim 14, wherein theintermediate layer is a positive photoresist, and the step of formingthe intermediate layer reserved region comprises: exposing theintermediate layer by a grey tone mask plate comprising an opaqueregion, a semi-transparent region and a transparent region; and forming,after a developing process, a first portion of the intermediate layerreserved region corresponding to the opaque region, a second portion ofthe intermediate layer reserved region corresponding to thesemi-transparent region and the intermediate layer unreserved regioncorresponding to the transparent region, wherein a thickness of thefirst portion is larger than a thickness of the second portion.
 16. Themethod according to claim 14, wherein the intermediate layer is anegative photoresist, and the step of forming the intermediate layerreserved region comprises: exposing the intermediate layer by a greytone mask plate comprising an opaque region, a semi-transparent regionand a transparent region; and forming, after a developing, a firstportion of the intermediate layer reserved region corresponding to thetransparent region, a second portion of the intermediate layer reservedregion corresponding to the semi-transparent region and the intermediatelayer unreserved region corresponding to the opaque region, wherein athickness of the first portion is larger than a thickness of the secondportion.